In order to fabricate a faucet valve with high rigidity and high corrosion resistance at a low cost, use of inexpensive alumina has been studied. A faucet valve has been known in which one valve body is coated with an amorphous carbon layer in order to improve the slidability of the faucet valve (for example, Japanese Patent Application Publication No. Hei 9-126239). Generally, in a case where amorphous carbon is applied to a slide member, as hard an amorphous carbon layer as possible is used for the coating to make full use of a “hard” property of the amorphous carbon. As a result, in the faucet valve in which one valve body is coated with an amorphous carbon layer, the other valve body, provided with no coating film, usually wears due to their sliding (for example, [0021] in Japanese Patent Application Publication No. Hei 9-292039, and [0027] in the Japanese Patent Application Publication No. 2004-183699). Wear of a valve body formed from a sintered body and provided with no coating film, however, involves a problem that a large amount of hard wear debris originating from the sintered body is produced to deteriorate the sliding characteristic with time.